The invention relates to a machine for rhythmic and reciprocal movement of workpieces and the like in the least two successive steps, having a carriage guided along its trajectory to move the pieces, and a drive for the carriage.
For intermediate stations on transfer lines, for example in the manufacture of motor vehicles, hoisting means capable of lifting the work in two steps are required. For this purpose, in known manner, means operated by compressed air or hydraulic cylinders are employed, wherein a guided carriage is displaced by means of two cylinders acting successively. However, the outlay of energy in the use of compressed air or hydraulic cylinders is high, and noise is also a problem. Furthermore, abrupt starting and braking are troublesome in many cases. Similar problems arise with known machines that move workpieces or other parts horizontally or obliquely, for example sheet-metal parts in pressing or stamping.
The object of the invention, then, is to provide a machine for rhythmic and reciprocal movement or workpieces and the like permitting gentle and rapid movement of workpieces and the like, permitting gentle and rapid movement in two or more steps with small outlay and lower energy input.